The present invention relates in general to barges and in particular to a new and useful locking mechanism for a self-dumping barge which includes at least one hydraulic cylinder for opening and closing a barge with a pivotable hook pivotally mounted on a support connected at one end of the piston rod for the cylinder. A bolt on which the hook engages is mounted on an end of the cylinder from which the piston rod extends.
For the opening and closing of self-dumping barges, hydraulic cylinders are usually employed which are located transversely in the area of the two ends of the vessel and are, as are their piston rods, attached to the two pivotable parts of the vessel through hinges. Consequently, these cylinders have to be fed through articulated pipe lines or hose lines. These lines and the seals inside the cylinders may cause leaks, which presents the danger that the barge may open, although only slightly, without it being intended, and lose the cargo if it is in the form of a bulk cargo. For this reason, in addition to the hydraulic actuating mechanism, a mechanical locking system is provided which is capable of keeping the barge closed in case of complete or partial failure of the hydraulic actuating system.
Such a mechanical locking system is, for example, known in the form wherein the hook support and the transverse bolt for engagement with the hook, are provided on arms approximately in the middle of the vessel, which are usually located below the hydraulic cylinders for effecting the pivoting motion. These arms require a sufficiently strong attachment to the hull, which requires reinforcing attachments, as do, in principle, the points of attachment of the hydraulic cylinders. Because of their location below the hydraulic cylinders, the locking means in question are not easily accessible, particularly as they are usually submerged, even when the vessel is not loaded.